"The Googlunaplex will house 35 engineers, 27,000 low cost web servers, 2 massage therapists and a sushi chef formerly employed by the pop group Hanson."
They went into great detail, including technical scripts, sketches and blueprints.
"The first non-trivial challenge is building a lunar base. Google began drawing up plans for the construction of a lunar facility in the Copernicus Crater early in 1998, when the company's founders Larry Page and Sergey Brin were still graduate students at Stanford University.
While their projections correctly predicted random spikes in search traffic due to wardrobe malfunctions, they failed to adequately factor in the hyperbolic trajectory of Britney Spears, which accelerated the rate of global search growth by a factor of seven."
See the Google April Fools Prank 2006 here.